The present invention relates to an exposure device for use in an image recording apparatus such as a copying machine.
A conventional exposure device for use in a copying machine has its back surface surrounded by a reflector in order to effectively collect light from a light source. In such a type, the light source and reflector are securely coupled together, thus making the necessary replacement of the light source significantly troublesome.
Photosensitive, pressure-sensitive recording mediums, are disclosed in Japanese Patent Application Kokai No. 58-23025, U.S. Pat. No. 4,399,209, and U.S. Pat. No. 4,440,846. U.S. Pat. No. 4,440,846 discloses a self-contained type recording medium in which an encapsulated chromogenic material or dye precursor and a developer material are codeposited on one surface of a single substrate as one layer or as two contiguous layers. U S. Pat. No. 4,399,209 discloses a transfer type recording medium in which the developer material is coated on a separate substrate as a separate developer or copy sheet. Such recording mediums, due to a low photosensitivity, require a large amount of light from a light source. A copying machine involving this type of recording medium uses a 1200 to 1400 W light source, almost twice as large as the one (500 to 600 W) used in an ordinary copying machine. As a result, a filament of a light source is frequently burnt out
Copending U.S. patent applications commonly assigned have been filed relating to the exposure device, U.S. Ser. Nos. 183,050 filed Apr. 19, 1988, 203,105 filed June 7, 1988, 204,239 filed June 9, 1988, and 218,219 filed July 13, 1988.